JPS62253656A - Molded polyarylene thioether article - Google Patents

Abstract

PURPOSE:A molded article, consisting of an uncrosslinked polyarylene thioether having a specific melt viscosity and specific potassium titanate fibers, having slight tackiness, improved processability and excellent mechanical strength as well as solder resistance and suitable for electronic part sealing materials. CONSTITUTION:A molded article, obtained by melt blending (A) 100pts.wt. uncrosslinked polyarylene thioether, preferably consisting mainly of p-phenylene groups having 10-200P melt viscosity (at 310 deg.C and 10,000/sec shear rate) with (B) 40-250pts.wt., preferably 55-190pts.wt. potassium titanate fibers, having 0.8-4mum, preferably 1.01-2mum average fiber diameter and 20-70mum, preferably 30-60mum average fiber length (preferably the surface thereof is treated with an aminosilane, etc.) to give pellets and preferably injection molding the pellets and having 100-400P melt viscosity, >=10kg/mm<2> flexural strength, >=6kg/mm<2> tensile strength and >=7kg.cm/cm Izod strength.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a melt viscosity (310°C, 10,000
(measured at a shear rate of 10 to 200 po1se)
The present invention relates to a polyarylene thioether molded product comprising an uncrosslinked polyarylene thioether and potassium titanate fibers having an average fiber length of 20 to 70 μm and an average fiber length of 0.8 to 4 μm. The molded product of the present invention is a polyarylene thiolether molded product that does not stick to processing machines particularly during melt processing and has practically required mechanical strength and solder resistance, and is suitable as an electronic component encapsulating material. It is.

Furthermore, the present invention relates to a solder-resistant sealing material for electronic components made of the molded article.

Conventional electronic components, such as ICs, LSIs, diodes, converters, etc., are sealed with resin for the purpose of maintaining electrical insulation, mechanical crushing, and preventing changes in characteristics due to external atmosphere. It is widely practiced. Conventional resin sealing uses thermosetting resins such as epoxy resin and silicone resin.
It was common to perform transfer molding using thermosetting resin, but since thermosetting resin was used, the molding time was long, storage management was difficult due to the pot life of the resin, and problems such as sluggishness and runners occurred. It has drawbacks such as the inability to reuse scrap. Attempts have been made to use polyarylene thioethe A/(hereinafter abbreviated as PATE), a thermoplastic resin that solves these problems, but pATW alone does not have the characteristics required for a sealing material. In other words, it is difficult to simultaneously satisfy the requirements of exhibiting high fluidity without causing viscosity in processing machines during molding, and ensuring that the encapsulant is crushed and has mechanical strength. A molded product made by mixing PATE with glass fiber, glass beads, silica, etc. as a filler material has been proposed. Kaisho 5
6-81953 etc.).

However, if a sufficient amount of glass fiber is mixed in to obtain the necessary mechanical strength, the melt viscosity of the PATE molded product becomes extremely high.
F) + where the element shifted (displaced) when it was sealed
There are disadvantages that the bonding wire may be deformed or cut, and that cracks occur frequently when the sealed electronic component is heated to 260''C for 10 seconds, resulting in lack of dust resistance.

In order to solve these drawbacks of conventional sealing materials, it has been proposed to use potassium titanate fibers as a filler, which are thinner and shorter than conventional fillers (Japanese Patent Laid-Open No. 1) fj59-
20910. % 1985-20911゜ 1987-2
15353, etc.), JP-A-59-20910
; JP-A-59-20911 and JP-A-59-21535
The potassium titanate fibers specifically used in 3 have a flat fiber diameter of 0.2 to 0.5 μm and an average stem length of 10 to 20 μm, and the potassium titanate fibers having such a shape are PATE If the sealing material is sufficiently filled, the adhesion to the metal will increase abnormally, and during melt molding, the sealing material will stick to the screw and sill and rotate as one, making molding impossible. In order to avoid this, if the filling tBB, 1 of the potassium titanate fibers is reduced, it will be difficult to obtain a sealing material with sufficient mechanical toughness! ! Becomes In addition, the calcium silicate fiber (forastonite) used in JP-A-59-20910 and JP-A-59-20911 has a fiber diameter of 1 to 3 μm and an RL fiber length of about 20 μrn, and is suitable for sealing materials due to its shape. However, due to the low strength of the fiber itself, it has not been found to be very effective in improving the mechanical strength of the encapsulant.

Furthermore, PATE used in the examples of JP-A-59-215353 is a crosslinked polymer exhibiting high melt viscosity. If such a high melting quality cross-linked polymer is used, it is easy to cause element displacement, deformation and breakage of the dending wire during sealing, and increase in viscosity. It has the disadvantage of being extremely fragile.

In order to solve the above-mentioned problems, the present inventors conducted intensive research and found that potassium titanate fibers with an average fiber diameter of 0.8 to 4.0 μm and an average fiber length of 20 to 70 μm were made into uncrosslinked FA.
We discovered that molded products containing TE K exhibit high fluidity during molding, do not stick to processing machines, and have mechanical strength comparable to sealants obtained from conventional thermosetting resins. Based on this knowledge, the present invention has been accomplished.

Structure of the Invention The molded article of the present invention has a 310" O1 shear rate of 10,000
Measured with Cs1 fcfd melt viscosity fbg 10-200
100 parts by weight of uncrosslinked PATE, which is pol sate;
and average fiber diameter 0.8-4〃m, average fiber length 20-70
It consists of 40 to 250 μm potassium titanate fibers, and its melt viscosity is 10 (1 to 400 poi@e
(310"O1 shear rate 10,000 (measured in seconds ν), bending strength 10kg/- or more, tensile strength 6kg
/mm2 or more, and the Izod strength is 7 kg/mm2 or more.

PATE#: of the molded product of the present invention is substantially a linearly polymerized polyarylene thioether.

Here, FAT Ilm is repeating unit +Ar-8+
.

(Ar: arylene group) as a main constituent.

The arylene group is one consisting of a 9 rough enylene group or 1? Those containing rough ethylene groups as a main component are preferable from the viewpoint of physical properties such as heat resistance, moldability and mechanical properties.

As the arylene group other than the rough enylene group, (R
: alkyl group (preferably lower alkyl group), nU1~
+O integer), p, p'-nophenylene-sulfonate group (
-C Lee SO2 (D-), pe P'-biphenylene group (++), I) + P'-sophenylene ether group c (
tri-0→C)-), p, p'-di7-dioxygenyl group (-@-co-@-) 310'O1 shear rate of PATE used in the present invention, o
o Melt viscosity measured in vf' in O is 10-200
pois@, preferably 20 to 100 pol IIs. I' exhibiting a melt viscosity of less than 10 pots.
Molded products made of ATE have poor melt processability, and
When PATE, which has a melt viscosity exceeding that of OIS, is used, the melt viscosity of the molded product is too high and does not exhibit high fluidity during sealing, resulting in inconveniences such as element displacement (displacement) and binding wire deformation and breakage. This is not preferable because it causes

≠X The PATE used in the present invention preferably has a substantially linear structure. For example, using an effective amount of a crosslinking agent (e.g., 1,2,4-trihalobenzene) during polymerization can result in subsequent crosslinking of PATE, or linear polymerization. Crosslinked f'ATE obtained by effectively crosslinking a remer by high temperature treatment in the presence of 02 or the like is not preferred as the PATE of the present invention. Molded products obtained using these crosslinked PATEs have a high melt viscosity during processing, which is not only unfavorable from the viewpoint of processability, but also the resulting molded products are usually extremely mechanically fragile and have poor physical properties. I don't like it from any aspect.

The above-mentioned linear PATEI'j can be economically produced by, for example, the method described in Japanese Patent Application Laid-open No. 7332/1983 filed by the present inventors. In addition, a large amount of carmenic acid described in Japanese Patent Publication No. 52-12240 is added to the polymerization system to form high molecular weight linear PATE.
A method for obtaining , etc. can also be used.

The potassium titanate fiber used as a filler in the present invention is a single crystal fiber represented by the general formula 2O-nTlo2 (n'=;6), and has an average fiber diameter of 0.8 to 4.0 μm, preferably 1.01 to 2 .0 μm, and the average fiber length is 2
It is 0 to 70 μm, preferably 30 to 60 μm.

Molded products made of potassium titanate fibers with an average fiber diameter of less than 0.8 μm, which were conventionally available, have significantly increased adhesion to metal surfaces, causing them to stick to the cylinders, screws, etc. of processing machines during molding. The screw rotates in unison with the screw, making molding impossible.

Also, to reduce stickiness, potassium titanate #I1.
If the filling amount of fibers is reduced, the mechanical strength of the molded product also decreases, making it unsuitable for practical use.

On the other hand, PATE molded products obtained using potassium titanate fibers having an average fiber diameter of 4.0 μm or more have insufficient mechanical strength.

Furthermore, if the average fiber length of the potassium titanate fibers is less than 20 μm, it becomes difficult to obtain a sealing material with sufficient mechanical strength. When it exceeds 70 μm, the melt viscosity of the frame molded product becomes significantly high.

When an element such as a capacitor is shifted (displaced) during sealing,
This causes inconveniences such as deforming or cutting the binding wires of PCs, ICs, etc. In addition, the average fiber length is 70 μm
It is not easy to industrially produce potassium titanate fibers exceeding 100%, so it is not practical.

That is, by using potassium titanate fibers with an average fiber diameter of 0.8 to 4.0 μm and an average fiber length of 20 to 70 μm as a filler for PATE, fluidity suitable for sealing, i.e., 100 to It becomes possible to obtain a restraining material which exhibits a melt viscosity of 400 polse and has a mechanical strength comparable to that of a magnetic sealing material obtained from a conventional thermosetting resin.

In addition, the above-mentioned potassium titanate fiber can be directly used as PAT.
Although it can be used by mixing EK, in order to increase the affinity with I'ATE, silane cassilling agents such as aminosilane, alkoxysilane, epoxyclane, mercagtosilane/acrylic 7rane, organic titanate coupling agents, or stearin are used. Potassium titanate fibers surface-treated with fatty acids such as acids can also be used. However, a surface treatment agent with low heat resistance or a low boiling point is undesirable because it decomposes or foams during melt-mixing or molding, thereby degrading the physical properties of the sealant.

It is important that the sealing material does not cause displacement (displacement) of the capacitor element, IC element, etc., deformation or cutting of the dangling wire, etc. during sealing.

For this purpose, it is important that the encapsulant exhibits high fluidity during molding.
It is necessary that the specific melt viscosity is 100 to 400 poise. If it is less than 100 pots, drawdown is likely to occur during melting, making it difficult to form into pellets or the like, which is not preferable. Also, 400
polms is not preferable because it does not exhibit high fluidity when melted and may cause displacement of the element or deformation or breakage of the mending wire during sealing.

Furthermore, sealed electronic components are required to not generate cracks or the like due to stress, temperature changes, etc. during soldering or use. For this purpose, the molded product must have a bending strength of 11
0kg/- or more preferably 12kl? /- or more, tensile strength 6 Y/- or more, preferably 7 kg/mm2 or more, X5
It is desirable to have a mechanical strength of 7 o'clock/17 mouths or more, preferably 8 o'clock/α or more.

The molded article of the present invention exhibiting the melt viscosity and physical properties as described above is
Per 100 parts by weight of the above-mentioned unframed & FATE, the above-mentioned potassium titanate fiber should be added at 40 to 250 parts by weight.The preferred weight is 55 parts by weight.
Obtained by filling up to 190 layers. If the amount of potassium titanate fibers is less than 40 parts by weight, the mechanical strength will be insufficient, and if it exceeds 250 parts by weight, the resulting molded product will have a significantly high melt viscosity. , Displacement (displacement) of the element during sealing, dangling wire 1. The composite sample of the present invention is made by mixing uncrosslinked PATE and potassium titanate fibers by a method that involves melting them, and forming a so-called "
Although it is usually obtained by converting the powder into a powder, it can also be obtained by tri-blending the powders of both components.

PATE is essentially a thermoplastic resin, and therefore, various additives can be added to the FATE molded product obtained according to the present invention according to those customary for thermoplastic resins. Specifically, for example, mica, TlO2
, 810 □, human t203, CaCO3, carbon black, talc, Ca5i02, MgC0, and powdered inorganic fillers such as glass can be melted and mixed to form a molded product. In addition, PE rubber, hydrogenated SB8 rubber, fluororubber, polyester elastomer, polyimide P1 polyamide,
Polif House 1 Etherketone, polysulfone, polyethersulfone, polyetherimide, polyarylene,? Lifuenylene ether, polycarbonate, polyethylene terephthalate, polybutylene terephthalate,
? Reacetal, propylene, ? Liethylene, AB
It can also be blended with C, polyvinyl chloride, polymethyl methacrylate, I-listyrene, vinylidene tetrafluoride, polytetrafluoroethylene, tetrafluoroethylene copolymer, etc. to form a molded product. In addition to these fillers, small amounts of stabilizers, nucleating agents, lubricants, rust preventives, coupling agents, mold release agents, water repellents, antioxidants, colorants, and the like can also be used.

Therefore, the molded product of the present invention includes not only a molded product made only of PATE and potassium titanate fibers, but also a molded product containing the various additives described above.

The molded product of the present invention can be produced using a normal molding method, that is, an injection molding method,
It is preferably molded by compression molding, extrusion molding, and especially injection molding, and has a bending strength of 10/- or more and a tensile strength of 6 &! Mechanical strength of /- or higher, mechanical strength of OD 7, AN/CS or higher, and excellent solder resistance (substantially no cracking is observed even when immersed in a 260°C solder bath for 10 seconds) This is a molded product showing the following.

Therefore, the molded product of the present invention is preferably used for sealing electronic components, such as capacitor elements, IC elements, L8I elements, transistor/sister elements, diode elements, etc., especially two capacitor elements.

Effects of the Invention Since the molded product of the present invention has a low melt viscosity, it is possible to prevent element displacement (
It is a molded product that is resistant to displacement (displacement), deformation or cutting of the bending wire, and has mechanical strength comparable to conventional molded products using thermosetting resins such as epoxy resins.

Also, the molded product of the present invention has a long molding time, which is a drawback of conventional thermosetting resin molded products. In addition to solving the difficulties in storage management and reuse of scraps caused by long lifespans, this method also reduces the high adhesion of molded products made from FAT IC and potassium titanate fibers to metals, which had been proposed in the past. Productivity during molding can be increased.

Furthermore, the sealed electronic component obtained from the molded product of the present invention has excellent mechanical strength and anti-sunder resistance.

The present invention will be described in more detail below based on Examples, but the present invention is not limited to these Examples.

Example 1? Production of Really Lenthioether (PATH) 2 m
In a titanium-lined autoclave, 1.0 OOkF of N-methylpyrrolidone and sodium sulfide (solid content 45.
93%) 2.2 kmot was charged and the temperature was raised to about 200°C to distill off water. Then p-dichlorobenzene 2
．． 45 kmol and 250 hN-methylpyrrolidone were charged and reacted at 210°C for 2 hours and then at 220°C for 4 hours. Next, add 7.45 kmol of pure water to make 26
The reaction was carried out at 3°C for 1.5 hours. After the reaction, the reaction mixture was filtered using a screen, washed several times with a 1.2% ammonium chloride aqueous solution at 50° C., and then dehydrated and dried to obtain PATH. The melt viscosity of the obtained PATE (polymer) was 4
0 poise (measured at 310° C., shear rate to, ooopo1).

40 parts by weight of Polymer A, 60 parts by weight of potassium titanate fiber A listed in Table 1 as an inorganic filler, 0.1 part by weight of calcium hydroxide, and 0.1 part by weight of 3-glycidoxypropyltrimethochynesilane were mixed in a mixer. After making it homogeneous, it is melt-mixed using a twin-screw extruder in the same direction to form a pellet-shaped PAT.
A molded product E was obtained. The melt viscosity of the obtained PATE molding was 170 polio (310°C1 shear rate 10.0
00ba1).

Using the pellet-shaped PATE molded product obtained as described above, test pieces for a bending test, a tensile test, and an Ir;od impact test were molded under the conditions shown below.

The bending test is based on ASTM D-790, and the tensile test is based on A.
STM D-638, IT, odllj impact test (no notch).

Each test shall be carried out in accordance with Human STM D-256.

The results of each test are shown in Table 2.

Molding machine: Injection molding machine manufactured by Japan Steel Works (JT-4O8) Molding conditions Cylinder temperature: 300-325-31. O″C
Money! 4. Temperature: 135" 0 screw per rotation i: 15 O~200 rpm Injection soil: 1
Holding pressure: 9 to 100 to 1200: 9 to 30 to 90 Injection time: 5 s@e The pellet-shaped PATE molded product obtained as described above was used to make a heat-resistant polyphenylene thioether film co/tensor element (Figure 1). was sealed under the following conditions to obtain a sealed molded product.

The capacitor element was sealed normally as shown in FIG. 2, and no deviation of the element, disconnection of the binding wire, or cracks as shown in FIG. 3 were observed.

Sealing molding machine 2 Injection molding machine manufactured by Japan Steel Works (JT-408)
Cylinder temperature: 270-310-310"0 Whole mold temperature: 150'0 Screw rotation speed: 150 rpm Injection pressure Near 50 Yu/d Holding pressure: 80 kg/1ffl Injection time: 5 δlle Cooling time: 5 sae Further, as described above. A solder resistance test was conducted on the encapsulated molded product obtained.

The molded product was immersed in a 260" O solder bath for 10 seconds and then observed for cracks, but no cracks were observed.

Examples 2 and 3 Melt viscosities of 150 pois and 220 pois were prepared as in Example 1 except that F'ATE (polymer A) and potassium titanate fibers were mixed as shown in Table 2.
Each poise pellet-shaped FATE molded product was obtained.

Furthermore, using each pellet-shaped PATE molded product, a bending test, a tensile test, a 1zod impact test, a sealing test, and a solder resistance test were conducted in the same manner as in Example 1.

The results are shown in Table 2.

Comparative Example 1 Melt viscosity of 260 polsa (measured at 310°C, shear rate 11, 000 shin 1) was prepared in the same manner as in Example 1 except that 2.27 kmol of p-dichlorobenzene was charged.
PATE (yN remer B) was obtained.

Example 1 was prepared using 870 parts by weight of polymer, 30 parts by weight of potassium titanate fiber, 1 part by weight of calcium hydroxide, and 0.1 part by weight of 3-glycidoxypropyltrimethochynesilane. A pellet-shaped PATE molded product was obtained using the same rod.

The melting quality of this PAT E molding is 650 poise
(310'C, n disconnection i10,000(!j)'''tem
ll fixed)! ? there were.

Example 1 Using the above pellet-shaped PAT E molded product,
Similarly, bending test, tensile test, l5od impact test,
A capacitor sealing test and a solder resistance test were conducted.

The results are shown in Table 2.

Comparative Example 2 N- in the chiku/lining autoclave of 27FLs
Methylpyrrolidone I, oooyu, soda sulfide (solid content 4
5.9:4%) 2.2 krnol was heated to about 200°C, water was distilled off, and the water was distilled off. Then 2.45 kmol of p-dichlorobenzene and 25 kmol of N-methylpyrrolidone
Prepare 0 klF and heat at 210℃ for 2 hours, then at 220℃ for 4 hours.
Allowed time to react. After the reaction, the reaction mixture was treated with Pate using a screen, washed several times with an aqueous solution of 1.2% ammonium chloride at 50°C, and then dehydrated and dried to obtain PATE.

The melt viscosity of the obtained PA'rg (polymer C) was 2p
oise (measured at 310°C, shear rate 1o, o o o han').

30 parts by weight of polymer, potassium titanate fiber 701
I part by weight, 7940.1 part by weight of cal hydroxide, and 0.1 part by weight of 3-glycidquinpropyltrimethoxysilane were melt-mixed in the same manner as in Example 1 to obtain a pellet-shaped PATE molded product. However, the drawdown was severe and it was difficult to make into pellets, and it was produced as a FATE molded product in the form of a block. The melt viscosity was 35 poia @ (310°C, shear rate rt
10. OOo@').

After pulverizing the above-mentioned lumpy PATE moldings, attempts were made to obtain test pieces and condenser encapsulation moldings in the same manner as in Example 1, but because they were extremely brittle, it was difficult to take out the molded products from the molding machine. The molded product was damaged and a normal molded product could not be obtained.

Comparative Examples 3 to 17 Each PATE molded product was produced in the same manner as in Example 1, except that the polymer obtained in Example 1 and the nine fillers shown in Table 1 were mixed in the proportions shown in Table 2. Perform each test±. Show me the results.

Table 1 Inorganic filler Note: fxam is based on the value listed in the catalog], and other fine fillers are based on the values determined by electron microscopy.

Vehicle presence

[Brief explanation of the drawings] Figure 1 shows the film capacitor element, Figure 2 shows the film capacitor element in Figure 1 in a normally sealed state, and Figure 3 shows the film capacitor element in Figure 1 in its sealed state. FIG. 4 is a schematic diagram showing a state in which the parts are sealed with occasional deviations (displacements). Procedural amendment December S, 1986"'7?jijt l El 1191 Ji R times 1
, Incident Display 1986 Patent Application No. 98488 2
, Title of the invention Polyarylene lentioether molded product 3, Relationship to the amended person's case Patent applicant name (110) Kureha Chemical Industry Co., Ltd. 4, Agent Yamada Building, 1-1-14 Shinjuku, Shinjuku-ku, Tokyo ( Postal code 160) Telephone (03) 354-862
35. Date of amendment order Proprietor 6. Number of inventions increased by amendment 7. Subject of amendment 8. Contents of amendment (1) "Processability" on page 14, line 9 in the specification. of"
Corrected as "Due to processing." ■ Ming@Shochu, page 15, line 4, rPE rubber,” rP
E-rubber, polyisobutylene,'' is corrected. C) In the specification, "polyetherketone" in lines 6 and 7 on page 15 is amended to "polyetheretherketone."

Claims (2)

[Claims] (1) 100 parts by weight of uncrosslinked polyarylene thioether with a melt viscosity of 10 to 200 poise (measured at a shear rate of 10,000 (seconds) at 310°C), an average fiber diameter of 0.8 to 4.0 μm, and an average fiber The melt viscosity is 100 to 400 poise (310°C, shear rate 10
,000 (seconds)^-^1), and the bending strength is 10kg/mm^2 or more, and the tensile strength is 6kg/mm^
2 or more and an Izod strength of 7 kg·cm/cm or more. (2) Melt viscosity is 10 to 200 poise (310℃,
A melt viscosity of 100 to 400 poise (measured at 310 °C, shear speed 1
0,000 (seconds)^-^1), and the bending strength is 12kg/mm^2 or more, and the tensile strength is 7kg/mm^2 or more.
An electronic component encapsulant made of a polyarylene thiolether molded product having a diameter of mm^2 or more and an Izod strength of 8 kg/cm/cm or more.